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1.
希土离子单硫代二苯甲酰甲烷配合物的合成及性质研究   总被引:2,自引:0,他引:2  
本文合成了单硫代二苯甲酰甲烷(HTDBM)和三价希土离子及路易斯碱(Q)的Ln(TDBM)4QH型配合物(Ln=除Ce外的La~Lu,Q=二乙基胺).测定了它们的摩尔电导值、红外光谱,可见—紫外光谱,核磁共振谱.观察到配合物是通过硫原子、氧原子同时与Ln3+离子配位.Ln-O键强于Ln-S键.在Nd3+、Pr3+、Ho3+、Er3+离子的该类配合物的可见吸收光谱中发现超灵敏跃迁现象.讨论了题述配合物作为核磁共振化学位移试剂的可能性.  相似文献   

2.
以二苯甲酰甲烷和4,4'-二甲基-2,2'-联吡啶为配体合成了一类单核稀土配合物[(dbm)_3Ln(dmbipy)](Ln=Eu(1)、Tb(2)、Ho(3)、Tm(4)和Yb(5))(Hdbm~-=二苯甲酰甲烷,dmbipy=4,4'-二甲基-2,2'-联吡啶)。单晶X-射线衍射分析表明五例配合物为同构,结晶于单斜晶系,P2_1/n空间群。配合物由3个dbm~-配体和1个dmbipy配体构成,中心Ln~(3+)离子位于四方反棱柱构型中。荧光测试表明,配合物1和2在可见光区出现了Eu~(3+)和Tb~(3+)离子的一系列特征发射峰,配合物3,4和5在近红外光区分别表现出Ho~(3+),Tm~(3+)和Yb~(3+)离子的特征发射峰。  相似文献   

3.
合成了以对叔丁基[6]芳烃(H6L)及DMF为配体,单一稀土RE3+(sm3+,Dy3+,Tb3+)及混合稀土Tb3+:(Ln3+(Ln3+=Gd3+,Y3+)为中心的5种稀土配合物.对其进行了元素分析、摩尔电导、红外光谱、差热分析、紫外光谱、核磁共振氢谱及荧光性能研究.荧光光谱的测试表明:Tb3+及其掺杂配合物具有较强的特征荧光,荧光惰性离子(Gd3+,Y3+)对Tb3+的荧光有增强作用,其中Y3+的敏化效果明显.  相似文献   

4.
利用2,6-二氟苯甲酸和1,10-菲咯啉作为配体分别与Tm~(3+)、Yb~(3+)离子在常温下反应,制得2个稀土配合物[Tm(dfba)_2(phen)(μ_2-dfba)]_2 (1)和[Yb(dfba)_2(phen)(μ_2-dfba)]_2 (2)(dfba~-=2,6-二氟苯甲酸根,phen=1,10-菲咯啉)。用元素分析、红外光谱对2个稀土配合物进行了表征,并用单晶X射线衍射确定了配合物的晶体结构;测定了配合物1和2的热稳定性。结构分析表明配合物1和2具有相似的晶体结构。每个Ln~(3+)与2个dfba~-配体和1个phen分子配位,形成[Ln(dfba)_2(phen)]~+结构单元,[Ln(dfba)_2(phen)]~+单元再通过2个不同的dfba~-配体桥联形成双核分子[Ln(dfba)_2(phen)(μ_2-dfba)]_2(Ln=Tm,Yb)。  相似文献   

5.
合成并通过红外光谱、元素分析、单晶及粉末衍射表征了3个一维配合物[Ln(HDTTA)_3(CH_3OH)_3]_(n )(Ln=Ce (1),Pr (2),Sm(3))的结构(D-H_2DTTA为(+)-二(对甲苯酰)-D-酒石酸)。单晶衍射结果表明,3个配合物同构,结晶于三方晶系手性空间群R3,在c方向呈现一维链状结构。荧光光谱表明由于D-H_2DTTA配体的激发态能级与Pr~(3+)和Sm~(3+)离子激发态能级接近,所以可以敏化2种离子的f电子在609 nm处的发光。此外,配合物1在紫外光照射下表现出良好的光催化降解染料亚甲基蓝的性质,在无外加试剂条件下160 min内降解率可达76%。  相似文献   

6.
希土离子-pmap-吡啶氧化物混配配合物的制备及性质研究   总被引:1,自引:0,他引:1  
合成了Ce(pmap)_4·2H_2O(pmap=1苯基-3 甲基-4-乙酰基-吡唑酮-5);Ln(pmap)_3·2H_2O·xC_2H_5OH(Ln=La-Nd,x=1;Ln=Sm,Eu-Lu,x=0)以及Ln(pmap)_3·L·H_2O(Ln=La-Lu;L=pyno, 3picno,4picno)等固体配合物,并对它们进行了热谱、电导、红外和可见——紫外光谱等的测试工作。观察到镧系收缩;吡啶氧化物上甲基的取代位置对混配配合物热稳定性的影响;Pr~(3 ),Nd~(3 ),Ho~(3 ),Er~(3 )离子配合物在可见区有超灵敏跃迁现象;从XPS光谱知不同希土离子结合能的对数值与原子序数间有直线关系。  相似文献   

7.
利用2,4,6-三甲基苯甲酸和5,5'-二甲基-2,2'-联吡啶配体在溶剂热的条件下成功合成出系列三元稀土超分子配合物[Ln(2,4,6-TMBA)_3(5,5'-DM-2,2'-bipy)]_2 (Ln=Pr 1,Nd 2,Sm 3,Eu 4,Gd 5,Dy 6),并对其进行了单晶X-射线衍射、元素分析、热重分析等一系列表征。研究结果表明配合物1-5同构,中心离子的配位数为9,配合物通过π–π堆积作用形成一维、二维的超分子结构。配合物6具有不同的结构,中心镝离子的配位数为8,分子间通过π–π堆积作用和C-H···O氢键形成一维、二维的超分子结构。利用TG/FTIR技术研究了配合物的热稳定性和热分解机理,荧光光谱表明配合物4可以发射出Eu~(3+)离子的特征荧光,同时对配合物6的磁性进行了初步探究。  相似文献   

8.
本文合成2,4-二羟基苯甲醛缩邻氨基苯甲酸Schiff碱(H~3L),以改进的合成方法得到此配体与镧系元素形成的九种新配合物.经分析确定其组成[Ln(H~2L)~2NO~3],(Ln=La、Pr、Nd、Sm、Gd、Dy、Ho、Er、Yb.以热重-差执分析、紫外、红外光谱以及核磁共振谱等表征,证明Schiff碱具有稳定的分子内氢键并以三卤形式同镧系离子形成稳定的共轭双六元螯合环.经研究表明,此系列配合物对甲基丙烯酸甲酯的聚合有明显的催化活性.  相似文献   

9.
研究与探讨了多(\)C=N-基空间不对称Schiff碱的合成, 合成了含有2个以上不同位置(\)C=N-基团的Schiff碱, 即四甘醇醛和2,4-二羟基苯甲醛缩双赖氨酸(TBLY)与稀土的配合物, 经元素分析、磁化率、光谱及1H NMR, 1H,1H COSY, 13C NMR谱等表征, 确定其组成为Ln3(TBLY)(NO3)3@nH2O (Ln = La, n = 3; Ln = Nd, n = 5; Ln = Gd, Dy, Yb, Y, n= 7). 以半经验量子化学AM1法计算并探讨了在红外光谱和核磁共振谱中所观察到的烯胺键的存在. 该类新Schiff碱配合物不需助催化剂即可单独催化聚合甲基丙烯酸甲酯(MMA), 转化率可达80%, 黏均分子量约为22万.  相似文献   

10.
本文报道了稀土丁二酸配合物Ln_2Su_3(Ln=Eu,Dy,Tm,Yb)在硫甘油(G_s)盐酸底物中的正负离子FAB谱,总结了它们的离子特征。对配合物在酸性硫甘油和甘油不同底物中的行为进行了比较,并提出了某些离子的可能形成过程。  相似文献   

11.
Eight 2D and 3D metal-organic framework (MOF) rare earth naphthalenedisulfonates have been obtained. The different geometry of the naphthalenedisulfonic acids used as connectors [(1,5-NDS) and (2,6-NDS)] gives rise to the three new structure types. In Ln(OH)(1,5-NDS)H2O, LnPF-1 (lanthanide polymeric framework; Ln=La, Nd, Pr, Sm and Eu), the lanthanide ion is octacoordinated. Its 3D structure is formed by (Ln2O14)-S-(Ln2O14) infinite chains, connected through complete NDS connectors. LnPF-2 (Ln=Nd), with the same empirical formula as the former, and the lanthanide in octa- and nonacoordination, owns an arrangement of sulfonate bridges and neodymium polyhedra that gives rise to a 2D structure. [Ln5(2,6-NDS)3(OH)9(H2O)4](H2O)2, LnPF-3 (Ln=Nd, Eu), demonstrates that it is possible to obtain a 3D structure with (2,6-NDS), when a greater Ln/connector ratio is employed. It is worth pointing out the existence, in this latter family of compounds, of a mu5-OH group, whose hydrogen atom is very close to one-sixth Ln atom (distance Ln...H=2.09 A). The materials, with high thermal stability, act as active and selective bifunctional heterogeneous catalysts in oxidation of linalool yielding cyclic hydroxy ethers. The absence of any 3D Nd-Nd magnetic interaction is explained due to the inner nature of 4f orbitals of Nd3+, which do not favor the magnetic exchange. The influence of the polymeric frame matrix results in a better photoluminescence efficiency for NdPF-1.  相似文献   

12.
Thermodynamic equilibria of complexes of 1,3-diamino-2-hydroxypropane-N,N,N',N'-tetraacetic acid (DHPTA) with heavy lanthanides (Tb3+, Ho3+ and Lu3+) in aqueous solution have been investigated with potentiometry, spectrophotometry, luminescence spectroscopy and nuclear magnetic resonance spectroscopy (NMR). The results identified three 1:1 Ln/DHPTA (Ln: Tb3+, Ho3+ and Lu3+) complexes with different degrees of deprotonation, LnL−, Ln(H−1L)2−, and Ln(OH)(H−1L)3−, where H−1 represents the deprotonation of the hydroxyl group between two methyliminodiacetate groups in the DHPTA structure. The alkoxide form of the DHPTA hydroxyl group directly binds to the lanthanide atom, forming highly strong chelation. The complex of Ln(H−1L)2− could be present as a dimeric or polymeric complex in solution.  相似文献   

13.
We have used EXAFS spectroscopy to investigate the inner sphere coordination of trivalent lanthanide (Ln) and actinide (An) ions in aqueous solutions as a function of increasing chloride concentration. At low chloride concentration, the hydration numbers and corresponding Ln,An-O bond lengths are as follows: La3+, N = 9.2, R = 2.54 A; Ce3+, N = 9.3, R = 2.52 A; Nd3+, N = 9.5, R = 2.49 A; Eu3+, N = 9.3, R = 2.43 A; Yb3+, N = 8.7, R = 2.32 A; Y3+, N = 9.7, R = 2.36 A; Am3+, N = 10.3, R = 2.48 A; Cm3+, N = 10.2, R = 2.45 A. In ca. 14 M LiCl, the early Ln3+ ions (La, Ce, Nd, and Eu) show inner sphere Cl- complexation along with a loss of H2O. The average chloride coordination numbers and Ln-Cl bond lengths are as follows: La3+, N = 2.1, R = 2.92 A; Ce3+, N = 1.8, R = 2.89 A; Nd3+, N = 1.9, R = 2.85 A; Eu3+, N = 1.1, R = 2.81 A. The extent of Cl- ion complexation decreases going across the Ln3+ series to the point where Yb3+ shows no Cl- complexation and no loss of coordinated water molecules. The actinide ions, Am3+ and Cm3+, show the same structural effects as the early Ln3+ ions, i.e., Cl- ion replacement of the H2O at high chloride thermodynamic activities. The Clion coordination numbers and An-Cl bond lengths are: Am3+, N = 1.8, R = 2.81 A; Cm3+, N = 2.4, R = 2.76 A. When combined with results reported previously for Pu3+ which showed no significant chloride complexation in 12 M LiCl, these results suggest that the extent of chloride complexation is increasing across the An3+ series. The origin of the differences in chloride complex formation between the Ln3+ and An3+ ions and the relevance to earlier work is discussed.  相似文献   

14.
The reaction of Ln(NO3)3(aq) with K3[Fe(CN)6] or K3[Co(CN)6] and 2,2'-bipyridine in water/ethanol led to eight trinuclear complexes: trans-[M(CN)4(mu-CN)2{Ln(H2O)4(bpy)2}2][M(CN)6].8H2O (M = Fe3+ or Co3+, Ln = La3+, Ce3+, Pr3+, Nd3+, and Sm3+). The structures for the eight complexes [La2Fe] (1), [Ce2Fe] (2), [Pr2Fe] (3), [Nd2Fe] (4), [Ce2Co] (5), [Pr2Co] (6), [Nd2Co] (7), and [Sm2Co] (8) have been solved; they crystallize in the triclinic space group P and are isomorphous. They exhibit a supramolecular 3D architecture through hydrogen bonding and pi-pi stacking interactions. A stereochemical study of the nine-vertex polyhedra of the lanthanide ions, based on continuous shape measures, is presented. No significant magnetic interaction was found between the lanthanide(III) and the iron(III) ions.  相似文献   

15.
The reaction of Ln(NO3)3(aq) with K3[Fe(CN)6] or K3[Co(CN)6] and 2,2'-bipyridine in water/ethanol led to 13 one-dimensional complexes: trans-[M(CN)4(mu-CN)2Ln(H2O)4(bpy)]n.4nH2O.1.5nbpy (Ln = Eu3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Lu3+; M = Fe3+, Co3+). The structures for [EuFe]n (1), [TbFe]n (2), [DyFe]n (3), [HoFe]n (4), [ErFe]n (5), [TmFe]n (6), [LuFe]n (7), [EuCo]n (8), [TbCo]n (9), [DyCo]n (10), [HoCo]n (11), [ErCo]n (12), and [TmCo]n (13) have been solved: they crystallize in the triclinic space group P and are isomorphous. They exhibit a supramolecular architecture created by the interplay of coordinative, hydrogen bonding, and pi-pi interactions. A stereochemical study of the eight-vertex polyhedra of the lanthanide ions, based on continuous shape measures, is presented. The Ln3+-Fe3+ interaction is antiferromagnetic in [DyFe]n and [TbFe]n. For [EuFe]n, [HoFe]n, [ErFe]n, and [TmFe]n, there is no sign of any significant interaction. The magnetic behavior of [DyFe]n suggests the onset of weak long-range ferromagnetic ordering at 2.5 K.  相似文献   

16.
大孔型腐植酸树脂的合成及其对重金属离子的螯合性   总被引:4,自引:0,他引:4  
交联的聚苯乙烯(PS)通过偶氮键—N=N—或酯、醚键与腐植酸(HA)相连接枝得珠状大孔型腐植酸树脂(HAR)。当HA/PSNH_2的重量比为0.7—1.0,PSN_2~+Cl~-偶联PH13时制得的偶氮型腐植酸树脂(AHAR)对重金属离子有优良的吸附性。延长PSCH_2Cl与HA的反应时间可提高酯醚型腐植酸树脂(EHAR)对Cu~(2+)的吸附量。红外光谱探讨了HAR的结构。AHAR的吸附容量为1.01mmol~(2+)Cd/g树脂,对Ni~(2+)、Mn~(2+)、Cu~(2+)、Co~(3+)、Zn~(2+)为0.6—0.53mmol离子/g树脂。重金属离子在AHAR上的分配系数为 Cu~(2+)(8.7×10~3)>Cd~(2+)(3.8×10~2)>Zn~(2+)(2.4×10~2)>Ni~(2+)(1.8×10~2)>Mn~(2+)(4.9×10)。 pH6.5时AHAR能定量吸附Cu~(2+)、Cd~(2+)、Ni~(2+)、Mn~(2+),并能用INHNO_3定量洗脱。AHAR可再生,重复使用,分析了四种天然水、自来水中痕量上述金属离子的浓度。  相似文献   

17.
采用水热法合成了5个稀土配合物[Sm2(bdbc)2(phen)4](1)和[Ln(bdbc)(phen)(H2O)][Ln=Eu(2), Gd(3), Tb(4), Dy(5), bdbc=(2-羧基苯氧基)苯-1,2-二羧酸根, phen=1,10-邻菲啰啉]. 配合物1是双核分子, 通过氢键和C—H…π作用进一步构筑成一维超分子结构; 配合物2~5是同构的一维双螺旋结构, 通过氢键和C—H…π作用进一步构筑成三维超分子结构. 配合物1, 2, 4和5呈现了Sm3+, Eu3+, Tb3+和Dy3+离子的特征发射, 分别对应于Sm3+离子的4G5/26HJ/2(J=5, 7, 9)、 Eu3+离子的5D07FJ(J=1—4)、 Tb3+离子的5D47FJ(J=6, 5, 4, 3)和Dy3+离子的4F5/26HJ/2(J=15, 13)跃迁. 对配合物4的荧光性质进行了表征, 结果表明, 配合物4可用作荧光探针以检测阳离子和苯甲醛.  相似文献   

18.
用分光光度法对镧系离子(Nd~(3+),Ho~(3+),Er~(3+))与1-苯基-3-甲基-4-三氟乙酰基吡唑酮-5(PMTFP)和二安替吡啉甲烷(DAM)水-乙醇溶液体系的研究以及对制备钕的相应配合物的元素分析证实:形成的三元配合物的的组成比为Ln~(3+):PMTFP:DAM=1:3:1。计算了相应配合物超灵敏跃迁的光吸收振子强度,并图示了它们之间的线性关系。研究了固态钕的三元配合物的红外吸收光谱和热稳定性。 镧系离子(Ln~(3+))同DAM和1-苯基-3-甲基-4-苯甲酰基吡唑酮-5(PMBP)等β-二酮以及Ln~(3+)与PMTFP和三辛基磷氧化物(TOPO)的三元配合物的研究已有报导。本文报导了Ln~(3+)(Nd~(3+)、Ho~(3+)、Er~(3+))-PMTFP-DAM体系中的超灵敏跃迁现象与配位作用,以及Nd(Ⅲ)-PMTFP-DAM配合物的合成、组成和性质。  相似文献   

19.
Colloidal, organic solvent-soluble Ln3+-doped LaVO4 nanoparticles have been synthesized by a precipitation reaction in the presence of (C18H37O)2PS2- as ligand, that coordinates to the surface of the nanoparticles. The materials are well soluble in chlorinated solvent such as chloroform. Energy transfer of excited vanadate groups has been observed for Ln3+ ions that emit in the visible and the near-infrared (Eu3+, Tm3+, Nd3+, Er3+, Ho3+, Dy3+, Sm3+, Pr3+), thus making it a very generic sensitization mechanism. The LaVO4 nanoparticles have a different crystal structure than bulk LaVO4 ones (xenotime instead of monazite), similar to YVO4 nanoparticles. This xenotime crystal structure results in a more asymmetric crystal field around the Ln3+ ions that is advantageous to their luminescence, for it increases the radiative rate constant, thus reducing quenching processes.  相似文献   

20.
利用缺位填充法合成了12个γ-[SiW10O36]8-夹心型稀土元素单取代多酸化合物K13[Ln(SiW10O36)2]·nH2O(Ln=La3+,Ce3+,Pr3+,Nd3+,Sm3+,Eu3+,Gd3+,Tb3+,Dy3+,Ho3+,Er3+,Yb3+).通过元素分析确定其组成,由红外光谱、紫外-可见吸收光谱、循环伏安及室温磁化率测定结果确认稀土离子与γ-[SiW10O36]8-相配位;183WNMR及荧光光谱结果则表明,稀土离子处于2个γ-[SiW10O36]8-构成的八配位环境中,标题化合物具有夹心型D2d对称性结构.  相似文献   

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